Effect of food and antacid on simvastatin bioavailability on healthy adult volunteers

Aims: The current research work was framed to identify and estimate the changes in pharmacokinetic data for oral simvastatin 40 mg in healthy adult volunteers during fasting condition and with simultaneous administration of food and antacids at a frequent interval. Materials and Methods: Nine healthy Malaysian male adult volunteers recruited into the present study. If study participants had a history of any major disease, they were excluded from the study. This study comprised of three groups with a crossover design in three blocks. Prior and after intake of drug, the blood samples (10 ml) were withdrawn and transferred to labeled glass tubes at a frequent interval. The blood sample was processed and the obtained serum was quantified by liquid chromatography–mass spectrometry/mass spectrometry method. Results: The pharmacokinetic data such as AUC0–24, Tmax, and Cmaxvalues were increased when the drug is administered along with drug or antacid. The elimination rate constant and volume of distribution do not found to have difference among the three groups. The t1/2of simvastatin was decreased when the drug is taken along with food but not with antacid or on empty stomach. The clearance of the drug is limited when the drug is administered along with antacid. Both antacid and food had the similar effect on simvastatin on various pharmacokinetic parameters such as AUC0–24, Cmax, Ke, Tmax, Cl, and Vd. Conclusion: The prolonged gastric residence time of simvastatin was produced by food and antacid by delaying gastric emptying which is offset by increased pH of the gastrointestinal tract. Thus, it leads to increased stability of lactone form of simvastatin and its absorption.